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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
631

Lier les présents aux absents : regards sur la condition d’exilé dans les littératures libano-québécoise et arabe contemporaine

Crépeau, Noémie 08 1900 (has links)
Les paramètres de l’exil, comme déplacement, se transforment aujourd’hui dans un contexte de mondialisation, interrogeant le rôle des nations alors que les sociétés impliquent de plus en plus de mobilité et de diversité culturelle. Cette condition d’exilé aux repères mouvants, inscrite dans une temporalité discontinue et dont l’expérience est toujours douloureuse, a donné lieu à une littérature prolifique dans le domaine des études littéraires au cours du 20e siècle. En quoi le 21e propose-t-il un regard différent sur cette condition ? Dans ce mémoire nous analyserons quatre œuvres contemporaines qui nous proposent différentes variations des transformations identitaires profondes qui caractérisent la condition d’exilé. Deux des grands axes autour desquels s’est articulée la condition d’exilé ont été développés par Edward Said, qui propose une posture critique et politique, et Julia Kristeva, qui présente l’exil comme une condition plutôt psychique. Suivant cette perspective analytique, l’autobiographie de Mourid Barghouti fait écho à la compréhension de l’exil telle que l’entend Said, en pleine autonomie instauratrice. Puis, le roman de Rawi Hage dans une expérience plus psychique de l’exil, plus traumatique et plus violente du vécu avant l’exil, suggère que le rapport avec le milieu environnant a un impact sur l’expérience de l’exil, alors que dans ce cas il reste dysfonctionnel, et qu’un rapport pathologique à l’existence peut ensuite se manifester. Ensuite, le roman d’Abla Farhoud expose la possibilité d’un dépassement de cette expérience pathologique de l’exil par la distance, celle de l’âge et de la prise de parole. Finalement, dans la pièce Incendies de Mouawad, l’expérience psychique de l’exil est dépassée à la fois par une traduction de l’indicible de la violence, par un retour sur les traumas précédant l’exil, et par un travail collectif – comme autres formes de distances. Cette dernière œuvre est donc porteuse d’une compréhension de l’exil impliquant une dimension psychique, tout en devenant critique et politique, telle que le révèlent les écrits de Jacques Rancière. À la lumière de ces analyses, la condition d’exilé réclame d’urgence un retour sur les traumas précédents, le trauma qu’est l’exil, afin qu’une autonomie, une créativité et un engagement s’en dégagent, dans une société, dans un monde plus grand que soi. Pour les trois derniers auteurs, c’est la société québécoise qui révèle à la fois une compréhension des problématiques majeures de la condition d’exilé et une ouverture face à celles-ci, en ce début de 21e siècle. / Exile is a condition of displacement and a phenomenon that affects great masses of people today. Although this experience exists since the proverbial beginning of time, its parameters are changing in the present context of globalization, which transforms the role of nations and where societies are characterized by greater mobility and cultural diversity. The profound psychological and cultural transformations of identity – inward and outward – to which people are confronted through displacement can be understood as a condition per se, an exilic condition. This condition with moving marks, and which develops in a discontinuous temporality and as a necessarily painful experience, has been the source of prolific literature and of literary studies in the 20th century and before. How, differently then, does the 21st century gaze at this condition ? In this thesis, four works are analyzed in which the authors present different visions of the exilic condition. Two main lines of thinking have been explored around this condition: Edward Said embraced a critical and political posture while Julia Kristeva conceived of exile in its psychological dimensions. Within these analytic perspectives, Mourid Barghouti’s autobiography has affinities with Said’s approach as it inaugurates an autonomous condition. Through Rawi Hage’s novel, a more psychological experience of exile is observed, one that is more violent and traumatic. It sheds light on the undeniable impact of the environment on the experience of exile in the host country. If the relation to the host country stays dysfunctional, a pathological attitude to the exilic experience may develop. Abla Farhoud’s novel explores the possible overcoming of the pathologies of exile through distance, age, time, and words, the distance needed for Dounia. Finally, the psychological limitations of exile can be overcome by translating the “unspeakable” in violence, by a return to the pre-exilic traumas, and by a collective sharing of this restorative work. Mouawad’s play also exposes the psychological dimension of exile, but it also maintains its critical and political ones. We observe through these analyses that the exilic condition demands a redressing of the traumas that preceded exile, understood as another trauma, so that the exiled can exist in an autonomous, creative and committed way in his or her society of adoption. For the last three authors, this society is Québec, which shows openness to, and comprehension of, the major issues of the exilic condition in the 21st century.
632

Déplacement, délocalisation et «dévoyage» dans quelques récits québécois contemporains

Crevier-Lalonde, Guillaume 09 1900 (has links)
Ce mémoire s’intéresse à l’écriture du voyage et du déplacement à travers l’exemple de cinq récits québécois contemporains. Nous étudions ici Voyage en Irlande avec un parapluie et Voyage au Portugal avec un Allemand de Louis Gauthier, Vers l’Ouest de Mahigan Lepage, Dix jours en cargo d’Isabelle Miron ainsi que Le sermon aux poissons de Patrice Lessard. Constatant que les voyages contemporains se sont délestés de l’expérience de l’exotisme et de la découverte, nous faisons l’hypothèse que l’écriture du déplacement se transforme. Nous analysons comment une expérience dysphorique du déplacement s’inscrit dans la description des lieux, la mise en récit et l’identité des narrateurs. À partir des travaux de Michel de Certeau (L’invention du quotidien) et de Marc Augé (Non-lieux : introduction à la surmodernité), nous nous intéressons, dans un premier chapitre, à la perception des lieux et à leur description. Notre parcours nous amène ensuite à examiner plus directement les modalités par lesquelles ces récits de la route produisent une continuité, métaphorique notamment. La troisième partie se concentre sur l’identité des narrateurs, qui tend à se construire ou à se déconstruire par rapport aux espaces qu’il parcourent. En nous servant des analyses d’images de Georges Didi-Huberman, nous examinons en conclusion comment ces différents aspects des textes produisent une « esthétique de la délocalisation », où les paysages et les lieux se constituent en écrans sur lesquels il est désormais possible de se projeter. / This thesis focuses on travel and displacement writing by exploring this theme into contemporary narrative in Quebec litterature. We study Voyage en Irlande avec un parapluie and Voyage au Portugal avec un Allemand (Louis Gauthier), Vers l’Ouest (Mahigan Lepage), Dix jours en cargo (Isabelle Miron) and Le sermon aux poissons (Patrice Lessard). By stating that travels don’t relay the experience of exotism and of discovery anymore, we make the assumption that the practice of narrating this new type of travels also changes. We analyse how this dysphoric experience of the travel reflects itself into the descriptions of the places, into the construction of a narrative, and into the construction of the identity. With the works of Michel de Certeau (The Practice of Everyday Life) and of Marc Augé (Non-Places: Introduction to an Anthropology of Supermodernity), our analysis questions, in a first chapter, the perception of spaces and their descriptions. Then, we examine more directly how these road narratives produce continuity. The third part focus on the identity of the narrator, that tends to be constructed and deconstructed by the landscape seen on the road. By referring to the analysis of images by Georges Didi- Huberman, we examine in our conclusion how those different aspects of the texts construct a « relocation » aesthetics in which landscapes and places become screens on which it is henceforth possible for the characters to project themselves.
633

Fibre-Optic Displacement and Temperature Sensing Using Coupling Based Intensity Modulation and Polarisation Modulation Techniques

Jason, Johan January 2013 (has links)
Optical fibre sensors are employed in the measurements of a number of different physical properties or for event detection in safety and security systems. In those environments which suffer from electromagnetic disturbance, in harsh environments where electronics cannot survive and in applications in favour of distributed detection, fibre-optic sensors have found natural areas of use. In some cases they have replaced conventional electronic sensors due to better performance and long-term reliability, but in others they have had less success mainly due to the higher costs which are often involved in fibre-optic sensor systems. Intensity modulated fibre-optic sensors normally require only low-cost monitoring systems principally based on light emitting diodes and photodiodes. The sensor principle itself is very elemental when based on coupling between fibres, and coupling based intensity modulated sensors have been utilised over a long period of time, mainly within displacement and vibration sensing. For distributed sensing based on intensity modulation, optical time domain reflectometer (OTDR) systems with customised sensor cables have been used in the detection of heat, water leakage and hydrocarbon fluid spills. In this thesis, new concepts for intensity modulated fibre-optic sensors based on coupling between fibres are presented, analysed, simulated and experimentally verified. From a low-cost and standard component perspective, alternative designs are proposed and analysed using modulation function simulations and measurements, in order to find an improved performance. Further, the development and installation of a temperature sensor system for industrial process monitoring is presented, involving aspects with regards to design, calibration, multiplexing and fibre network installation. The OTDR is applied as an efficient technique for multiplexing several coupling based sensors, and sensor network installation with blown fibre in microducts is proposed as a flexible and cost-efficient alternative to traditional cabling. As a solution to alignment issues in coupling based sensors, a new displacement sensor configuration based on a fibre to a multicore fibre coupling and an image sensor readout system is proposed. With this concept a high-performance sensor setup with relaxed alignment demands and a large measurement range is realised. The sensor system performance is analysed theoretically with complete system simulations, and an experimental setup is made based on standard fibre and image acquisition components. Simulations of possible error contributions show that the experimental performance limitation is mainly related to differences between the modelled and the real coupled power distribution. An improved power model is suggested and evaluated experimentally, showing that the experimental performance can be improved down towards the theoretical limit of 1 μm. The potential of using filled side-hole fibres and polarisation analysis for point and distributed detection of temperature limits is investigated as a complement to existing fibre-optic heat detection systems. The behaviour and change in birefringence at the liquid/solid phase transition temperature for the filler substance is shown and experimentally determined for side-hole fibres filled with water solutions and a metal alloy, and the results are supported by simulations. A point sensor for on/off temperature detection based on this principle is suggested. Further the principles of distributed detection by measurements of the change in beat length are demonstrated using polarisation OTDR (POTDR) techniques. It is shown that high-resolution techniques are required for the fibres studied, and side-hole fibres designed with lower birefringence are suggested for future studies in relation to the distributed application. / Fiberoptiska sensorer används för mätning av ett antal olika fysikaliska parametrar eller för händelsedetektering i larm- och säkerhetssystem. I miljöer med elektromagnetiska störningar, i andra besvärliga miljöer där elektronik inte fungerar samt i tillämpningar där distribuerade sensorer är att föredra, har fiberoptiska lösningar funnit naturliga applikationer. I vissa fall har de ersatt konventionella elektroniska sensorer på grund av bättre prestanda och tillförlitlighet, medan de i andra sammanhang har haft mindre framgång huvudsakligen på grund av den i många fall högre kostnaden för fiberoptiska sensorsystem. Intensitetsmodulerade fiberoptiska sensorer kräver normalt endast billiga utläsningssystem huvudsakligen baserade på lysdioder och fotodioder. Principen för sådana sensorer baserade på koppling mellan fibrer är mycket enkel, och denna typ av sensorer har haft tillämpningar under en lång tid, främst inom mätning av positionsförändring och vibrationer. För distribuerade intensitetsmodulerade sensorer har system baserade på optisk tidsdomän-reflektometer (OTDR) och skräddarsydda sensorkablar funnit tillämpningar i detektion av värme/brand, vattenläckage och kolvätebaserade vätskor. I denna avhandling presenteras, simuleras, testas och utvärderas praktiskt några nya koncept för kopplingsbaserade intensitetsmodulerade fiberoptiska sensorer. Från ett lågkostnads- och standardkomponentperspektiv föreslås och analyseras alternativa lösningar för förbättrad prestanda. Utveckling och installation av en temperatursensor för en industriell tillämpning, innehållande aspekter på sensormultiplexering och nätverksbyggande, behandlas. OTDR-teknik används som en effektiv metod för multiplexering av flera kopplingsbaserade sensorer, och installation av sensornätverk genom användning av blåsfiberteknik och mikrodukter föreslås som ett flexibelt och kostnadseffektivt alternativ till traditionell kabelinstallation. Som en lösning på förekommande upplinjeringsproblem för kopplingsbaserade sensorer, föreslås en ny sensorkonfiguration baserad på koppling mellan en fiber och en multikärnefiber/fiberarray och med ett bildsensorsystem för detektering. Med detta koncept kan ett högpresterande, upplinjeringsfritt sensorsystem med ett stort mätområde åstadkommas. Sensorsystemets prestanda har analyserats teoretiskt med kompletta systemsimuleringar, och en experimentell uppställning baserad på standardfiber och en kamera av standardtyp har gjorts. Simuleringar av möjliga felbidrag visar att systemets experimentella prestanda främst begränsas av skillnader mellan den modellerade och den verkliga optiska effektfördelningen. En förbättrad modell för effektfördelningen föreslås och utvärderas experimentellt. Det visas att prestanda är möjlig att förbättra ner mot den teoretiska gräns på 1 μm som erhållits vid systemsimuleringar. Möjligheterna att använda fyllda hålfibrer och polarisationskänslig mätning för detektering av temperaturgränser studeras i syfte att komplettera befintliga fiberoptiska värmedetektorsystem. Förändringen i fiberns dubbelbrytning vid övergångstemperaturen mellan vätske- och fast fas för ämnet i hålen visas och bestäms experimentellt för hålfibrer fyllda med vattenlösningar respektive en metallegering, och resultaten understöds också av simuleringar. En punktsensor för temperaturdetektering baserad på denna princip föreslås. Vidare visas principerna för distribuerad detektering genom registrering av förändringen i dubbelbrytning med polarisations-OTDR (POTDR). Det visas att OTDR-teknik med hög spatial upplösning behövs för övervakning av de studerade fibrerna, och hålfibrer utformade med lägre dubbelbrytning föreslås för framtida studier av tillämpningen.
634

We Are Not Going Anywhere : An ethnographical study of (im)mobility in Jordan

Berg, Hanna January 2018 (has links)
In present time, to be mobile, to be able to physically move from point A to point B is something taken for granted by a small minority of the world’s population, while the vast majority are caught within or between borders. How did we reach to this point? This study examines the lived experiences of (im)mobility in Jordan. It captures the experiences of Syrians who live in Jordan and who have been denied mobility because of their flight from their homeland. By means of an ethnographical approach this study challenges conventional conceptions of what it means to be displaced. Situating the understanding of displacement in relation to the modern nation state, territorial boundedness, national identity and geographical categorizations it ultimately lays the foundation for conceptualizing the relative human (im)mobility and its links to a historical past. Through travelling and living in Jordan periodically between 2017-2018, totalizing approximately 6 months, conducting semi-structured interviews and engaging in everyday social and contextual encounters, this study offers a more multifaceted understanding of what it means to be (im)mobile in present time, as additional to conventional scholarship. It ultimately demonstrates that displacement as we understand it today is inadequate and simplified, and as we reassess its components we are able to reconceptualize the understandings of relative human (im)mobility.
635

[en] DETERMINATION OF RELATIVE PERMEABILITY CURVES OF EMULSIONS AND OIL / [pt] DETERMINAÇÃO DAS CURVAS DE PERMEABILIDADE RELATIVA NO ESCOAMENTO DE EMULSÕES E ÓLEO

BERNARDO SOARES ENGELKE 19 September 2012 (has links)
[pt] Durante a vida de um campo de petróleo, diferentes métodos de recuperação podem ser usados para manter a pressão do reservatório e aumentar a eficiência de varrido. O método mais utilizado é o de injeção de água. Porém, a eficiência deste método é limitada devido à alta razão de mobilidade entre água e óleo, o que leva a formação de canais preferenciais de escoamento da água. Agentes de controle de mobilidade são usados para minimizar este efeito. Dentre eles, emulsões óleo-água apresentam benefícios em custo, compatibilidade e eficiência. Alguns estudos indicam uma melhor eficiência da fase aquosa com menor razão água-óleo nos poços produtores. A fase dispersa da emulsão é capaz de bloquear as gargantas dos poros e alterar o caminho do escoamento no meio poroso, melhorando não apenas a eficiência de varrido como também a de deslocamento. O objetivo deste trabalho é estudar a injeção de emulsão óleo-água e entender os mecanismos que envolvem seu uso como um agente de controle de mobilidade. O efeito micro e macroscópico da injeção de emulsão será avaliado experimentalmente através da medida das curvas de permeabilidade relativa de emulsão óleo-água e óleo em amostras de arenitos para diferentes concentrações da fase dispersa da emulsão, distribuição do tamanho de gota e número de capilaridade. / [en] During the life of an oilfield, different oil recovery methods may be used to maintain the reservoir pressure and increase sweep efficiency. The method most commonly used is water injection. The efficiency of the method is limited due to the high mobility ratio between water and oil, that leads to water fingering. Mobility control agents can be used to minimize this effect. Among them, oil-water emulsions (O-W) present several benefits in cost, compatibility and efficiency. Several studies indicate a better sweep efficiency of the water phase with lower water-oil ratio in the production wells. If properly designed, the dispersed phase of the emulsion may block the pore throats and change the flow path at the pore level, improving not only the sweep but also the displacing efficiency. The aim of this research is to study oil-water emulsion flooding and understand the mechanisms involving its use as a mobility control agent. The micro and macro effect of the emulsion injection is going to be evaluated experimentally by measuring the relative permeability curves of water-oil emulsions and oil in sandstone cores for different dispersed phase concentration, droplet size distribution and capillary number.
636

Mondialisation et marché du travail : étude sur les emplois exposés et abrités en France / Globalization and the labor market : A study of tradable and non-tradable jobs in France

Frocrain, Philippe 28 November 2018 (has links)
On oppose traditionnellement les emplois industriels et les emplois de services. L’interpénétration croissante de l’industrie et des services rend cependant cette distinction de plus en plus inopérante. À l’heure de la globalisation, il apparaît en revanche pertinent de distinguer les emplois exposés à la concurrence internationale de ceux qui en sont abrités, que l’on trouve à la fois dans l’industrie et dans les services. Cette thèse analyse dans un premier temps les évolutions et les caractéristiques des emplois exposés et abrités en France. Quels sont les emplois exposés et abrités ? Se distinguent-ils en termes de qualifications, salaires, évolutions de la productivité ? Comment sont-ils répartis sur le territoire ? Elle étudie ensuite les interdépendances entre ces deux catégories d’emplois, en évaluant empiriquement l’effet d’entraînement de l’emploi exposé sur l’emploi abrité au niveau des zones d’emploi de France métropolitaine. L’étude s’intéresse enfin à un échantillon de salariés licenciés suite à la fermeture d’un site de production. Elle tente de déterminer si le risque de licenciement, et les coûts qui lui sont associés, sont plus élevés dans le secteur exposé que dans le secteur abrité. / The distinction between manufacturing and service jobs has lost some of its relevance due to the growing interpenetration between industrial and service activities. On the other hand, globalization has made it increasingly necessary to distinguish between jobs exposed to international competition (tradable jobs) and those not exposed to it (non-tradable jobs), found in primary, secondary and tertiary sectors. This thesis begins by analyzing the developments and characteristics of tradable and non-tradable employment in France. Which jobs are tradable and which are non-tradable? Are they different in terms of skills, wages, and productivity? How are they distributed around the country? It then studies the interdependencies between these two categories of employment, making an empirical evaluation of the local multiplier effect of tradable jobs on non-tradable jobs in French local labor markets. Lastly, the thesis focuses on workers laid off due to firm closure. It sets out to determine whether the risk of job displacement, and the associated costs, are higher in the tradable sector than in the non-tradable sector.
637

Development-induced displacement and resettlement : a narrative inquiry into the experiences of community members physically displaced from a farm to a town in Mpumalanga, South Africa.

Smithen, Caitlin 17 September 2014 (has links)
Although expected to be beneficial to society, development projects, such as dam construction and mining, often result in the physical displacement of marginalized groups. This is known as Development-Induced Displacement and Resettlement (DIDR) and often has far-reaching negative consequences for the affected peoples (APS). These include further marginalization, increased poverty, identity deprivation and socio-psychological stress. While decades of knowledge inform theory and practice on the mitigation of these consequences, the psycho-socio-cultural (PSC) impoverishment that may result from DIDR is often left unaddressed. Furthermore, qualitative knowledge of the experiences of people affected by DIDR is lacking. This research study aimed to produce an in-depth understanding of how DIDR affects the PSC well-being and identity construction of APS. The research took the form of a qualitative case study, whereby a social constructionist, narrative method of inquiry was used to analyse and gather data. This involved undertaking in-depth, individual interviews with a small sample of APS who had been resettled from a farm to a town in Mpumalanga by a mining house. Briefly, it was found that, contrary to the prevalent finding that DIDR causes further impoverishment, the resettlement actually resulted in development for the APS and as such enhanced their PSC well-being and contributed positively to their identity construction. However, the complexity inherent in resettlement was highlighted, as the participants revealed that the resettlement had not come without some socio-economic costs. It is believed that the findings from this study will complement existing knowledge on DIDR, and inform the design and implementation of Relocation Action Plans (RAPs) that better mitigate the negative PSC effects of DIDR.
638

[en] GIANT MAGNETOSTRICTIVE MATERIALS APPLIED TO CONTACTLESS DISPLACEMENT SENSORS / [pt] APLICAÇÃO DE MATERIAIS COM MAGNETOSTRICÇÃO GIGANTE EM SENSORES DE DESLOCAMENTO SEM CONTACTO

CLARA JOHANNA PACHECO 13 December 2007 (has links)
[pt] A magnetostricção é a propriedade dos materiais ferromagnéticos de se deformarem pela presença de um campo magnético externo. Trata-se de uma propriedade inerente ao material, que não muda com o tempo. Materiais que apresentam deformações da ordem de 10-3 são conhecidos como materiais de magnetostricção gigante (GMM). Esta dissertação de mestrado estuda a aplicação destes materiais em sensores de deslocamento onde não há contacto entre o elemento cursor (um ímã) e o elemento sensor (GMM). O princípio de funcionamento consiste em aplicar um gradiente de campo magnético ao GMM que está fixo. O gradiente de campo magnético é gerado por um ímã preso ao componente ou estrutura na qual se quer medir o deslocamento. As variações no campo magnético no material GMM originados pelo deslocamento do ímã (estrutura), provocam uma deformação no GMM, que é detectada com extensômetros do tipo Strain Gauge ou Redes de Bragg. Neste trabalho apresenta-se a caracterização da deformação de GMM em relação a um campo constante aplicado, e análises do seu comportamento para diferentes geometrias. Efeitos de pressão, polarização com um segundo ímã, e diferentes gradientes de campo magnético são também estudados. É observado um comportamento local para a deformação quando a medida é realizada em diferentes regiões do GMM. Os resultados obtidos permitiram a medição de deslocamentos de alguns micra estando o elemento sensor a até 10 mm de distância do elemento cursor. / [en] Magnetostriction is a property of ferromagnetic materials to deform in the presence of a magnetic field. Magnetostriction is an inherent property of magnetic materials, which is unchangeable with time. Materials exhibiting strains in the order of 10-3 are known as giant magnetostrictive materials (GMM).In this dissertation we study the application of these materials in displacement sensors where there is not contact between the cursor element (magnet) and sensor element (GMM). Its principle of operation consists of applying a magnetic field gradient to a GMM located at a fixed position. The magnetic field gradient is produced by a magnet attached to the component or structure in which the displacement will be measured.The variation on the magnetic field in the GMM position originated from the displacement of the magnet, results in a strain in the GMM that can be detected with a Strain Gauge or Bragg Grating extensometers. In this work is presented the characterization of the strain on GMM cuboids against a constant magnetic field and the analysis of its behavior for different geometries. Effects of pressure, polarization with a second magnet, and different gradients of magnetic field are also studied. It is observed a local behavior for strains when it is measured in different regions of GMM cuboid. The results obtained allow us to measure displacements of about few micra when the sensor is at a distance of 10 mm from the cursor element.
639

Em percurso / En route

Nakamura, Alline Alves 23 September 2016 (has links)
Em percurso se constitue de imagens, sobretudo fotografias, feitas entre 2008 e 2016, nos trajetos e percursos de algumas cidades por onde passei. Somam-se ao conjunto as fotos realizadas em espaços privados e nas ruas por onde faço minhas andanças. Parto de minha experiência em registrar as paisagens, lugares e espaços durante os meus deslocamentos, principalmente entre as cidades de Atibaia-SP e a capital paulista, através das janelas de veículos particulares e transportes coletivos. As recordações das viagens em família e de ter feito desenhos em pequenos cadernos na década passada, dentro dos ônibus ou de memória, estruturam a minha compreensão visual atualmente. A câmera fotográfica torna-se um instrumento de desenho. Após a captura das fotografias, os procedimentos de tratamento, edição e impressão fazem parte do processo de construção das imagens. Os relatos escritos em breves notas sobre algumas vivências trazem informações que podem colaborar na percepção do que é visto. Ao mesmo tempo, as palavras têm sua autonomia, assim como as imagens. / Em percurso (En route) is made of images, mainly photographs, shot between the years of 2008 and 2016, along the paths and routes of some cities I\'ve been to. Some other pictures, depicting private spaces and streets that I walk on, have also been added to the set. I depart at my experience in registering landscapes, places and spaces as I go from one place to another, especially from the city of Atibaia-SP to the capital of the State, through the windows of private cars or public transportation. The memories of family trips and of drawings made in small notebooks in the last decade, inside buses or out of my memory, organize my current visual understanding. The photography camera becomes a drawing device. After shooting, the treatment procedures, editing and printing are part of the process of building images. The short written notes about some experiences offer information that may contribute to the perception of what is seen. At the same time, the words are autonomous as well as the images are.
640

Otimização das formas de cascos de deslocamento em relação a sua resistência ao avanço. / Displacement hull optimization regarding to ship wave resistance.

Alvarez, Rodrigo Loureiro Prado 11 February 2008 (has links)
Devido à constante necessidade de construções de novas embarcações, quer seja pela demanda do mercado, quer seja pela renovação da frota, o desenvolvimento de programas computacionais que auxiliem na fase inicial de projeto torna-se bastante útil. Assim, o desenvolvimento de um procedimento de análise que permita obter formas de melhor desempenho vem a agregar valor nesta etapa de conceituação da geometria do navio. O trabalho aqui apresentado tem como objetivo discorrer sobre um método capaz de otimizar a geometria de um casco de deslocamento conhecido em relação a sua resistência ao avanço, sem perder, porém, as suas características principais, como corpo paralelo médio, por exemplo. Para tanto, dentro deste processo de otimização já estão inseridas algumas restrições que garantem a viabilidade da solução final, tais como variação máxima no comprimento, no volume total e na estabilidade do navio. A modelagem da embarcação pode ser feita através de funções B-Splines cúbicas de superfície, cujos pontos de controle (parâmetros inerentes à função) podem ser modificados de tal sorte a atingir um valor ótimo para a resistência ao avanço. Esta, por sua vez, será obtida através da soma de duas parcelas, sendo uma referente ao atrito e outra à geração de ondas pelo casco. Como a maior parte da resistência provém desta segunda parcela para a velocidade de projeto a ser considerada (alto número de Froude), a redução da resistência total pode ser assumida como conseqüência da diminuição da resistência devido à geração de ondas, a qual pode ser obtida através da formulação apresentada por Michell, em 1898. O cálculo das propriedades hidrostáticas como deslocamento, estabilidade ( KM transversal) e superfície molhada, usada para cálculo da resistência ao avanço, pode ser encontrado fazendo-se uso do cálculo vetorial. O procedimento a ser descrito foi desenvolvido em linguagem C++ (modelagem do casco) e com o auxílio do MATLAB® (método de otimização). Este trabalho foi realizado no Dep. de Eng. Naval e Oceânica da USP. / Due to an increasing necessity of building new vessels, whether by new orders or fleet renewal, the development of computational programs that could allow optimization of hull shapes is always helpful, saving project time and ensuring better performance at sea. Thus, the development of a synthesis procedure that allows obtaining shapes with better performance adds value to the initial phase of the ship geometry concept. The work to be presented herein objectives the presentation of a methodology to achieve optimal shapes for displacement hulls in relation to the total resistance, starting from an initial geometry given, describing hull form and applying specific constraints to optimization problem with the purpose of guarantee a reliable solution. Therefore, inside this optimization process there are included some constraints that ensure a feasible final solution, as maximum variation of ship length, total volume and stability. Hull geometry is described by using B-Spline surface functions and the ship wave resistance is calculated using Michell\'s formulation as a first approximation of the total resistance for high Froude numbers. Once vessel surface is well defined, B-Spline parameters are varied until an optimal form is attained and the minimum resistance is achieved. It can take a little time to calculate, depending on ship definition (number of buttocks and waterlines) and the problem complexity (number of constraints and variables). Ship displacement and other hydrostatic properties as stability, given by transversal KM , wetted surface, used for calculating ship resistance, can be obtained using the vectorial calculus. This work has been developed using C++ language, except the optimization process which makes use of a MATLAB® function called fmincon. This study has been held at the Department of Naval and Ocean Engineering of the University of São Paulo, Brazil.

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